The present invention relates generally to inkjet printers, and more particularly to an inkjet printing system using a single motor for print media advance and carriage motion.
A conventional inkjet printing system includes a printhead and an ink supply which supplies liquid ink to the printhead. The printhead, commonly referred to as a pen, ejects ink drops through a plurality of orifices or nozzles and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Typically, the orifices are arranged in one or more arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the printhead and the print medium are moved relative to each other.
As illustrated in FIG. 1, a conventional inkjet printing system 200 includes a print media transport assembly 210 which moves and/or routes the print medium through a print media path, a carriage assembly 220 which moves the printhead relative to the print medium, and a service station assembly 230 which maintains functionality of the printhead. The print media transport assembly typically includes a paper pick-up assembly 212 which brings the print medium into the printing system, a drive or feed roller assembly 214 which advances the print medium through the printing system, and a paper path motor 216 which operates the paper pick-up assembly and the feed roller assembly. The carriage assembly typically includes a carriage 222 which carries the printhead and a carriage motor 224 which operates the carriage. Furthermore, the service station assembly typically includes a service station motor 232 which operates functions of the service station assembly.
FIG. 2 illustrates a method 300 of operation of the conventional inkjet printing system. At step 302, the inkjet printing system gains operational control of a print job. Next, at step 304, the printhead is uncapped and wiped by operation of the service station assembly. Operation of the service station assembly in step 304 requires operation of the service station motor. Next, at step 306, the print medium is pulled into the printing system by operation of the print media transport assembly. Operation of the print media transport assembly in step 306 requires operation of the paper path motor. Next, at step 308, the carriage is moved to a xe2x80x9cReadyxe2x80x9d position by operation of the carriage assembly. Operation of the carriage assembly in step 308 requires operation of the carriage motor.
To begin printing the print job, the print medium is moved into position by operation of the print media transport assembly at step 310. Operation of the print media transport assembly in step 310 requires operation of the paper path motor. Next, at step 312, the carriage is moved across the print medium by operation of the carriage assembly to print a print swath. Operation of the carriage assembly in step 312 requires operation of the carriage motor. As such, steps 310 and 312 are repeated until the print job is completed.
Once the print job is completed, the print medium is kicked from the printing system by operation of the print media transport assembly at step 314. Operation of the print media transport assembly in step 314 requires operation of the paper path motor. Next, at step 316, the carriage is moved to a xe2x80x9cRestxe2x80x9d position by operation of the carriage assembly. Operation of the carriage assembly in step 316 requires operation of the carriage motor. Finally, at step 318, the printhead is wiped and capped by operation of the service station assembly. Operation of the service station assembly in step 318 requires operation of the service station motor.
Operation of the conventional inkjet printing system, therefore, requires operation of three separate motors. More specifically, operation of the conventional inkjet printing system requires operation of a paper path motor, a carriage motor, and a service station motor. Unfortunately, the requirement of three motors adds to the size, complexity, and cost of the conventional inkjet printing system.
Accordingly, a need exists for an inkjet printing system which is smaller or performs more functions for the same size, simpler to manufacture, and/or less expensive to manufacture. In particular, a need exits for an inkjet printing system which utilizes a single motor to control operation of multiple printing functions such as moving a print carriage, advancing a print medium, and/or maintaining a printhead.
One aspect of the present invention provides an inkjet printing system. The inkjet printing system includes a print media transport assembly adapted to route a print medium through the inkjet printing system, a carriage assembly adapted to hold an inkjet printhead assembly and traverse the print medium, and a motor operatively coupled to both the print media transport assembly and the carriage assembly. As such, the motor is adapted to drive both the print media transport assembly and the carriage assembly.
In one embodiment, the motor is configured to sequentially operate the print media transport assembly and the carriage assembly.
In one embodiment, the motor is adapted to advance the print medium and move the inkjet printhead assembly. In one embodiment, the motor is adapted to advance the print medium in a first direction and move the inkjet printhead assembly in a second direction, wherein the second direction is substantially perpendicular to the first direction. In one embodiment, the motor is configured to rotate a portion of the print media transport assembly in the first direction and reciprocate a portion of the carriage assembly in the second direction.
In one embodiment, the print media transport assembly includes a first shaft and at least one roller mounted on the first shaft, and the carriage assembly includes a second shaft and a carriage slidably mounted on the second shaft. As such, the at least one roller is adapted to contact the print medium and the carriage is adapted to carry the inkjet printhead assembly.
In one embodiment, the inkjet printing system further includes a service station assembly adapted to at least one of wipe, cap, and uncap the inkjet printhead assembly. As such, the motor is operatively coupled to and adapted to drive each of the print media transport assembly, the carriage assembly, and the service station assembly.
In one embodiment, the inkjet printing system includes a first power transmission path defined between the motor and the carriage assembly, and a second power transmission path defined between the motor and the print media transport assembly. As such, the motor is operatively coupled to the carriage assembly via the first power transmission path and operatively coupled to the print media transport assembly via the second power transmission path.
In one embodiment, the inkjet printing system includes a third power transmission path defined between the motor and a service station assembly of the inkjet printing system. As such, the motor is operatively coupled to the service station assembly via the third power transmission path. In one embodiment, the third power transmission path includes the second power transmission path.
In one embodiment, the inkjet printing system includes a first power transmission arrangement interposed between the motor and the carriage assembly. The first power transmission arrangement includes a first coupling configured to selectively connect and disconnect the motor with the carriage assembly. In one embodiment, the first power transmission arrangement further includes a power transmission element configured to transfer rotational power of the motor to a reciprocatable element of the carriage assembly.
In one embodiment, the inkjet printing system includes a second power transmission arrangement interposed between the motor and the print media transport assembly. The second power transmission arrangement includes a second coupling configured to selectively connect and disconnect the motor with the print media transport assembly. In one embodiment, the second power transmission arrangement further includes a gear train configured to transfer rotational power of the motor to a rotatable shaft of the print media transport assembly.
In one embodiment, the inkjet printing system includes a third power transmission arrangement interposed between the motor and a service station assembly of the inkjet printing system. The third power transmission arrangement includes a third coupling configured to selectively connect and disconnect the motor with the service station assembly. In one embodiment, the third power transmission arrangement further includes a gear train configured to transfer rotational power of the motor to a movable pallet of the service station assembly.
In one embodiment, the inkjet printing system further includes a first sensor adapted to detect a position of the inkjet printhead assembly and generate a first position signal in response thereto, a second sensor adapted to detect a position of the print medium and generate a second position signal in response thereto, and an electronic controller adapted to receive the first position signal and the second position signal. As such, the electronic controller is adapted to control at least one of coupling and operation of the motor in response to at least one of the first position signal and the second position signal.
Another aspect of the present invention provides a method of printing on a print medium with an inkjet printing system including an inkjet printhead assembly. The method includes routing the print medium through the inkjet printing system via a print media transport assembly and traversing the print medium with the inkjet printhead assembly via a carriage assembly. As such, the steps of routing the print medium and traversing the print medium include operatively coupling and driving both the print media transport assembly and the carriage assembly with a single motor.
The present invention provides an inkjet printing system which utilizes a single motor to control operation of multiple printing functions. As such, the single motor controls operation of a carriage assembly of the inkjet printing system and a print media transport assembly of the inkjet printing system. In addition, the single motor also controls operation of a service station assembly of the inkjet printing system.